What is Adenoma ?

Adenoma refers to a collection of growths (-oma) of glandular origin. Adenomas can grow from many organs including the colon, adrenal, pituitary, thyroid, etc. These growths are benign, but some are known to have the potential, over time, to transform to malignancy.

Adenoma is a benign tumor of epithelial tissue, such as the mucosa of stomach, small intestine, and colon, in which tumor cells form glands or gland-like structures. In hollow organs (digestive tract), the adenoma grows into the lumen -Sadenomatous polyp or polypoid adenoma. Depending on the type of the insertion base, adenoma may be pedunculated (lobular head with a long slender stalk) or sessile (broad base).

The adenomatous proliferation is characterized by different degrees of cell dysplasia (atypia or loss of normal differentiation of epithelium) irregular cells with hyperchromatic nuclei, (pseudo)stratified nuclei, nucleolus, decreased mucosecretion, and mitosis. The architecture may be tubular, villous, or tubulo-villous. Basement membrane and muscularis mucosae are intact.


1 Colon

Adenomas of the colon are quite prevalent. They are found commonly at colonoscopy. They are removed because of their tendency to become malignant and lead to colon cancer. Removal is simple and painless at the time of colonoscopy.

2 Adrenal

Adrenal adenomas are common (1 in 10 people have them), benign and asymptomatic. They are found on CAT scan of the abdomen, usually not as the focus of investigation; they are usually incidental findings. About one in 10,000 is malignant. Thus, a biopsy is rarely called for. Followup images in three to six months can cofirm the stability of the growth. The malignant growth of the adrenal is called adrenal adenocarcinoma .

3 Thyroid

About one in 10 people are found to have solitary thyroid nodule s. Investigation is required because a small percentage of these are malignant. Biopsy usually confirms the growth to be an adenoma, but sometimes, excision at surgery is required, especially when the cells found at biopsy are of the follicular type.

4 Pituitary

Pituitary adenomas are commonly seen in 10% of the population. A lot of them remain undiagnosed. Treatment is usuallly surgical, to which patients generally respond well. A subtype, prolactinoma, is seen commonly in women, and is frequently diagnosed during pregnancy as the hormone progesterone increases its growth. Medical therapy ( bromocriptine) generally suppresses prolactinomas; progesterone antagonist therapy has not proven to be successful.